Justin Bieber, right, and Nicki Minaj perform at the 40th Anniversary American Music Awards on Sunday, Nov. 18, 2012, in Los Angeles. (Photo by Matt Sayles/Invision/AP)

 

              Justin Bieber, right, and Nicki Minaj perform at the 40th Anniversary American Music Awards on Sunday, Nov. 18, 2012, in Los Angeles. (Photo by Matt Sayles/Invision/AP)
Justin Bieber, right, and Nicki Minaj perform at the 40th Anniversary American Music Awards on Sunday, Nov. 18, 2012, in Los Angeles. (Photo by Matt Sayles/Invision/AP)